Gating Analog SYSREF with Real-Time Signals (Gen 3/DFE) - 2.6 English

Zynq UltraScale+ RFSoC RF Data Converter v2.6 Gen 1/2/3/DFE LogiCORE IP Product Guide (PG269)

Document ID
Release Date
2.6 English

In the previous MTS implementation section, certain API is used to gate the analog SYSREF signal, or one-shot analog SYSREF signal is required when some dynamic events (that is, NCOs frequencies) need to be updated simultaneously.

With Gen 3/DFE, there are two groups of real-time signals the dacX_sysref_gate and adcX_sysref_gate that are introduced for analog SYSREF gating on chip.

For single chip use case, these real-time signals can replace the SYSREF gating API. For MTS across multiple RFSoCs, all related SYSREF gating signals should assert to gate analog SYSREF input first, waiting for all updates be armed then deassert simultaneously. Thus, the next raising edge of analog SYSREF will trigger the armed dynamic updates. In this design, all related SYSREF gating signals must be well-aligned both inside and outside of AMD Zynq™ UltraScale+™ RFSoCs. With this design, the SYSREF clock can be AC or DC coupled.